Track position regulation of scanning transducer - made relative to information track selected on carrier with multiple recordings

摘要

The analogue signal emitted by the scanning transducer is digitized by a threshold comparison. The analogue signal (S) is subjected to several comparisons with various thresholds (VA and VB). The digital signals (SD and SB are compared and the scanning transducer is centred above the information track in such a manner that the differences obtained during the comparison of various digital signals (SD and SB are at a minimum. The analogue signal (S) is subjected to at least three comparisons with various thresholds. The digital signal (SD obtained by comparison with a predetermined threshold (VA) is selected a s a reference signal with which the other two digital signals are compared.